This invention relates to an image forming device with separable units and more particularly to a mechanism by which an image forming device such as a copier is made separable into an upper unit, a middle unit and a lower unit.
Some image forming devices such as copiers are made separable into two or more units such that cleaning and other maintenance work inside the device can be carried out easily. An image recording device disclosed in Japanese Pat. No. 59-66247, for example, is comprised of an upper unit containing an optical system, a middle unit containing a photosensitive drum and a lower unit containing a portion of the passageway along which recording paper is transported such that the upper unit can be separated from the middle unit when the optical system is cleaned or other maintenance work is performed and the middle unit can be separated from the lower unit when a jammed sheet is removed or the passageway for paper is cleaned.
With a prior art device of this type, however, the upper unit may open up with respect to the middle unit, for example, while the user is removing a jammed sheet of paper after opening the middle unit with respect to the lower unit. In such a case, the balance of the device as a whole may be lost and the device may fall as a result.